gillilajstd



(No Model.)

B. T. GILLILAN-D.

AUTOMATIG SHUNT FOR MAGNETO ELECTRIC GENERATORS.

Patented Feb. 18,1883.

INVENTOR.

UNITED. STATES PATENT OFFICE.

EZRA T. GILLILAND, OF INDIANAPOLIS, INDIANA.

AUTOMATIC SHUNT FOR MAGNETO-ELECTRIC GENERATORS.

SPECIFICATION forming part of Letters Patent No. 272,234, dated February13, 1E 83.

Application tiled October 10, 18852. (No model.)

To all whom it may concern:

Be it known that I, EZRA T. GILLILAND, of the city of Indianapolis,county of Marion, and State of Indiana, have invented certain new anduseful Improvements in Automatic Shunts for Magneto-Electric Generators,of which the following is a specification.

The object of my said invention is to provide a shunt formagneto-electric generators which shall be strictly automatic-t 0.,wherein the magnetic force existing in the generator itselt' shalloperate to keep it short-circuited at all times, except when power isapplied to rotate the armature.

The invention consists essentially in combining with the rotary armatureof a magnetoelectric generator at contact spring or bar, which isattached to said armature at one end and is in Contact with thecylinder-head at the other, thus bridging the space between saidarmature and said head and permitting the electric current to freelypass from one to the other,thusshort-circuitingthehelixatalltimes,except when the contact is broken, which may be done by means of anotchor notches (or pieces of insulating material) in thefacc ol' thecylinder-head over which said spring passes, as will be hereinafter moreparticularly described.

Referring to the accompanying drawings, which are made a part hereof,and on which similar letters of reference indicate similar parts, Figure1 is a horizontal sectional view on the dotted line a z of a call-signalbox for telephonic purposes containing a magnetoelectric generatorprovided with myinvention; Fig. 2,.a vertical section thereof at such apoint as will show the armature in elevation; Fig.3, a central verticalsection of the'saine on the dotted line 3/ 3 on an enlarged scale; Fig.4, a transverse section of Fig. 3, looking to the left from the dottedline 0000, and Fig. 5 a perspective View of the armature andcylinder-heads.

In said drawings the portions marked A represent the lower ends ofthepermanentor horseshoe magnets of a magneto-electric generator; B, thepole-pieces thereof; 0, the rotary armature; D, the spring or bar, whichis an essential feature of myimproved shunt; E, the cylinder-heads; F,contact-springs bearing against the points extending from the ends ofthe ar mature, and G H wires or strips representing the incoming andoutgoing lines.

The magnet-s A, pole-pieces B, armature C, contact-springs F, andline-connections G H may be constructed in any ordinary or suitableform, (the form shown being, however, preferred) and as the constructionof such apparatus generallyis well understood need no specialdescription. Tile particular form shown will be described in anotherapplication for Letters Patent which I intend to make.

The spring or bar D is attached to the pin 0, over which the electriccurrent usually passes out of the armature, or to a cross-bar attachedthereto, and extends out until its end rests against the cylinder-head.This spring is preferably provided with a projection, d, which makes abetter contact-point and operates with less wear and friction than thebare spring would if so used. The effect of this spring while itscontact with the cylinder-head is maintained is, as will be readilyseen, to reuder inoperative the insulating material and to permit theelectric current to pass through the armature from one end to the otherwithout passing through the helix, or, in other words, to cut out saidhelix.

The cylinder-head E is preferably constructed with a raised annularportion, as shown, in which are notches 0. When the point d on thespring D passes these notches the contact between said spring and thehead is broken and the electric current is forced to pass in the usualcourse through the helix. Small pieces of insulating material may ofcourse be used instead of the notches 6; but I regard the latter as themore desirable.

As is well known to electricians, the electric current passes otf t'roma rotary armature just at the time when said armature leaves the.polepieces, or, in other words, when it changes polarity. For thisreason the notches e are in line with the center of the pole-pieces, andthe spring D is set at right angles with the faces of the armature, orin equivalent relative positions, so that the point (I of the springpasses through the open space formed by said notch at exactlythe timewhen the electricity is given oli' by the armature, and thus saidelectricity is forced to go by the regular ordinary route,notwithstanding; the usual short-circuited condition of the helix.

By the arrangement above described the shunt is also rendered automatic.The magnetic attraction holds the faces of the armature adjacent to thepole-pieces, except when other force, as the turning of the crank, isemployed to move said armature. As, when the armature is in thisposition, the point of the spring or bar D is in contact with thecylinderhead, thereby cutting out the helix, it will be readily seenthat this device is strictly automatic, being; cut out at all times Whenat rest by reason of being magnetically held, so that there is a contactbetween the spring I) and the cylinder-head.

The arrangement described keeps the helix effectually cut out at alltimes, except when the generator is in actual use, and thus accomplishesby simple and strictly automatic means that which has heretofore eitherrequired a distinct operation on the part of the user of the machine ora considerable addition to the mechanical construction of the machineitself.

Having thus fully described my said invention, what I claim as new, anddesire to secure by Letters Patent, is-

1. The combination, with the rotary armature of a magnetoelectricmachine, of a contact-piece, I), connected to the insulated pin in saidarmature and adapted to rest against the cylinder-head, saidcylinder-head being provided with notches or insulating points overwhich said contact-piece shall pass, whereby the shunt or short circuitnormally maintained by the action of said contact-piece is broken andthe circuit through the armature temporarily established, substantiallyas set forth.

2. The combination of the armature 0,0011- tact-piece D, andcylimler-heads E, the latter having notches or pieces of insulatingmaterial therein, substantially as described, and for the purposesspecified.

3. A shunt for IHE'IQIlGtOGlEGtIlC generators, the essential featureswhereof are a contactpiece, I), for bridging the insulating materialwhich surrounds the pin over which the current from the helix leaves thegenerator, and meansot'brealiing the contact periodicallydurlug, therotation ot'the armature, said contactpiece being; arranged,substantially as described, to beheld in position to form the shunt bythe magnetic force of the generator, except when forcibly moved to adili'erent position.

In witness whereof I have hereunto set my hand and seal, atIndianapolis, Indiana, this 6th day of October, A, D. 18:52.

EZRA T. GILLIL A1?

